Grazing Incidence Interferometer
4GRP LAZER GRAZER is a non-contacting Grazing Incidence Interferometer.
. . the first modestly priced Interferometer for measuring flatness
of semi-matte or matte-finished surfaces. The Model 4GRP also permits the
measurement of parts which are much larger than its 4-inch aperture because
is measures flatness across a 4 inch by 16 inch elliptical beam path as
4GRP Phase-Shifting LAZER GRAZER
If you don't need the 4-inch aperture of the Model 4GRP, please look at our Model 2GRP and 2GRP. The principle is the same... the size and the price are different.
Our 4-inch aperture LAZER GRAZER, Model 4GRP Interferometer operates under the control of Durango Interferometry Software which provides a live interferogram on the computer monitor. The user can select from a rich palette of graphics, text files and reports. For further Information click on Durango.
Typical Durango Screen, shown below, showing live interferogram, histogram, and OPD plot. Durango permits the user to select from a wide array of graphics, text files and customized reports.
Note that the live image shows interference fringes on the surface of the test sample while providing a 3-D image of the part.
This unique display is a feature available only with Graham's Grazing Incidence Interferometers! This capability is of enormous value in the interpretation of test pieces with complex geometry.
substrates easily tested
With a normal incidence Fizeau
The Lower drawing shows the interferogram of the same part using a grazing incidence Fizeau interferometer.
With a grazing angle of 14.48 degrees, 1 fringe = 1 wave. The grazing incidence interferogram shows that the part is either concave or convex by: 4 fringes = 4 waves = 2.53 microns
of the wide variation in sample thickness encountered, it is essential
to make provision for the sample surface to be totally covered by the incident
laser beam. By providing a height adjustment for the tilt table, samples
of various thickness can be examined. After the appropriate tip-tilt
adjustment has been made, the tilt-table may be raised or lowered as required
for the sample to fully encounter the beam.
Non-contacting Grazing Incidence Interferometers like the 4GRP series of instruments open the door for the flatness measurement of semi-matte and matte finished surfaces -- surfaces which otherwise are not reflective enough to evaluate with an interferometer.
The Model 4GRP Phaseshifting LAZER GRAZER is available now. This turnkey system is complete with 2.41GHz All-inOne Computer with a 19.45 inch diagonal screen., data acquisition board, phase-shift, and Durango Interferometry Software.
Further Information, Prices, Delivery, call Gordon Graham today at